I will show an example of running iPerf to test network bandwidth using UDP Multicast.
Continue reading “iPerf Mulicast”Tag Archives: Performance
Zabbix. Upgrading the database to primary keys
Starting with Zabbix 6.0, primary keys are used for all tables in new installations, but since I upgraded Zabbix server to version 6.4, I had to manually update the tables after the upgrade.
Before updating, first of all, open the menu “Report” – “System Information” and make sure that the keys are not used, this will be indicated by the entry – “Database history tables use primary key – No”, if the keys are used, then this entry simply will not be.
Continue reading “Zabbix. Upgrading the database to primary keys”Messages net_ratelimit: X callbacks suppressed
Once I found the following messages in the dmesg log:
Continue reading “Messages net_ratelimit: X callbacks suppressed”Script to bind Intel NIC interrupts to processor cores
I will give the script code from Intel to bind interrupts of Intel network adapters to processor cores, and also show examples of its use:
Continue reading “Script to bind Intel NIC interrupts to processor cores”Taskset – bind process to CPU cores
By default, processes use all the processor cores, but sometimes it is necessary to release the 0 core, which is usually the most loaded, or assign some processes only to the second CPU, etc., in this case, taskset will help.
Continue reading “Taskset – bind process to CPU cores”Increase the port range net.ipv4.ip_local_port_range
There is a possibility that on a highly loaded server, such as a proxy or router, with a very large number of connections, free ports in the allocated range may run out, so you need to look at the current number used and, if necessary, increase the net.ipv4.ip_local_port_range value.
Continue reading “Increase the port range net.ipv4.ip_local_port_range”Configuring logrotate to rotate logs
Logrotate is used to control the logging system, compress log files, delete old ones, etc.
The configuration is located at /etc/logrotate.d/ and /etc/logrotate.conf.
Testing a DHCP server with dhcpperf
dhcpperf is a DHCP load testing tool.
Continue reading “Testing a DHCP server with dhcpperf”How to change innodb_flush_method in MySQL
innodb_flush_method defines the method for flushing data from RAM to disk.
Continue reading “How to change innodb_flush_method in MySQL”High CPU load on Cisco Nexus 3064
Once I discovered on the graphs a large burst of Multicast packets on one of the ports of the Cisco Nexus 3064 switch, while the CPU load increased to 30%, before that it was 12% with L2 traffic of 13 Gbit/s.
Continue reading “High CPU load on Cisco Nexus 3064”